OpenAI Codex logo

OpenAI Codex

OpenAI API platform for developers

Lets you build applications with OpenAI models using API endpoints, starter apps, and cookbooks.

AI developer platformsapi accessmodel integrationdeveloper toolscode examples
OpenAI Codex homepage screenshot
OpenAI Codex homepage (platform.openai.com), captured 2026-10-02

What is OpenAI Codex?

OpenAI Codex is the platform where you sign in to use the OpenAI API. It is the entry point for developers who want to add AI capabilities to their own software. The platform provides access to OpenAI models, along with the tools to integrate them into your projects.

To get started, you sign up or log in with an OpenAI account. You can use your email, or continue with Google, Apple, Microsoft, or your phone. Once inside, you can explore the API Reference to see endpoints and parameters, check Starter Apps for sample applications, and read Cookbooks for practical examples and best practices.

This platform suits developers and teams who build software and want to embed AI features. The website focuses on technical resources rather than end-user tools. It does not state pricing details or specific model names on this page, so you will need to check the developer docs for that information.

OpenAI Codex features

  • API Reference: Explore all endpoints and parameters to understand how to call OpenAI models.
  • Starter Apps: Sample applications built with the API to help you begin coding quickly.
  • Cookbooks: Practical examples and best practices for common use cases and workflows.
  • Account sign-in: Use email, Google, Apple, Microsoft, or phone to access the platform.
  • Developer Docs: Official documentation to guide you through building on the API.

What you can do with OpenAI Codex

  • Build a chatbot that uses OpenAI models in your own app.
  • Create a content generation tool for your website.
  • Integrate AI-powered features into your existing software.
  • Learn how to use the API with starter apps and cookbooks.

How to get started with OpenAI Codex

  1. Go to the OpenAI Platform website and sign up or log in with your OpenAI account.
  2. Choose a sign-in method: email, Google, Apple, Microsoft, or phone.
  3. Open the API Reference, Starter Apps, or Cookbooks to start building.

Tips for better results with OpenAI Codex

  • Start with the Starter Apps and Cookbooks to see working code before writing your own, saving time and avoiding common API mistakes.
  • Use the API Reference to check exact endpoints and parameters for Codex, ensuring your requests match the documented structure and expected responses.
  • Test your integration in a development environment with sample keys first, then move to production once you confirm behavior and error handling.
  • Review the Developer Docs for Codex to understand authentication, rate limits, and model capabilities before scaling your app.

OpenAI Codex pricing

OpenAI Codex’s homepage does not list prices. Check platform.openai.com for current plans.

What to check before you rely on OpenAI Codex

  • Confirm your account has access to the models you need, since the platform page does not list specific model names or availability.
  • Check the Developer Docs for pricing details, as the website does not state costs or plan limits on this page.
  • Verify data handling and privacy policies for your use case, since the page only links to Terms of Use and Privacy Policy without specifics.

Who OpenAI Codex is for

OpenAI Codex suits software developers, API integrators and tech teams. If that is not you, the AI developer platforms below may fit better.

Similar tools compared with OpenAI Codex

ToolWhat it isPricing
OpenAI CodexOpenAI API platform for developersSee website
SiVideoAPIUnified API for top AI video modelsFreemium
OpenSIAI model comparison and pricing toolSee website
OpenRouterUnified API for many AI modelsFreemium
OllamaRun open models locally or cloudFreemium

OpenAI Codex FAQ

What is OpenAI Codex?

OpenAI Codex is the platform where you sign in to use the OpenAI API. It gives developers access to OpenAI models and resources like API documentation, sample apps, and cookbooks to help them build applications.

Is OpenAI Codex free?

The website does not state pricing on this page. You will need to check the developer docs or your account dashboard for details on any free tier or paid plans.

Who is OpenAI Codex for?

It is for developers and technical teams who want to integrate OpenAI models into their own software. You need an OpenAI account to get started.

What can I build with OpenAI Codex?

You can build applications that use OpenAI models, such as chatbots, content generators, or any AI-powered feature. The platform provides starter apps and cookbooks with practical examples to guide you.

What can I export or connect with OpenAI Codex?

The OpenAI Codex platform page does not mention any export options or external connections. It focuses on providing API access, starter apps, and cookbooks. For details on integrations or data export, check the developer docs linked on the platform.

Which devices or platforms does OpenAI Codex run on?

OpenAI Codex is a web-based platform, so you can access it through a browser on any device with internet. The page does not specify mobile apps or desktop software. You can sign in from your computer, tablet, or phone using the supported login methods.

Does OpenAI Codex require an account to use?

Yes, OpenAI Codex requires you to sign up or log in with an OpenAI account. You can use your email, or continue with Google, Apple, Microsoft, or your phone. Once signed in, you can access the API reference, starter apps, and cookbooks.

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